The present invention relates generally to fire barriers and more particularly to fire and cycle tested, inside-mounted, one-step, drop-in installation, one-piece continuous construction, multi-directional fire barriers for multi-directional architectural expansion joints, and tools for installing said fire barriers.
The background information discussed below is presented to better illustrate the novelty and usefulness of the present invention. This background information is not admitted prior art. The particular versions of the invention as described below are provided, in part, as illustrative and exemplary. Thus, the described versions should not be taken as limiting. Additionally, the invention is not limited to the examples provided.
Modern building codes require building design to take into account the stresses that buildings often experience, such as extreme or repetitive changes in temperature, the force of wind impinging on the building, forces due to seismic events, settling of subsoil, remodeling of the building, excavation on or near the site, and other forces. To accommodate these stresses, buildings must now be constructed with code mandated spaces between wall, floor, and ceiling structures. These spaces, referred to as “expansion joints,” allow differential building movement to take place without risking damage to the whole structure.
While expansion joints do serve the function for which they are employed, that is to improve the integrity of the structure when the building units are subjected to contraction or expansion, expansion joints also present a major risk to the structure. During a fire the expansion joint spaces act as chimney flues providing pathways for gases, flame, and smoke to spread rapidly throughout the structure creating what is known as the “chimney effect.” To counter this effect, building codes for public and commercial structures generally require fire barriers to be installed in the expansion joint spaces to prevent flames and smoke from passing through the joint spaces. Although various fire barriers are presently available, there are no tested, ready to be installed, fire barriers ready for use in multi-directional expansion joint spaces.
Logically, fire barriers should be classified into two major structural categories: straight-line barriers and multi-directional barriers. Presently available barriers are referred to as “straight line barriers.” These barriers are designed to fit into straight-line expansion joint spaces, such as the joint space that occurs between two adjacent building wall units. An expansion joint space, however, often intersects one or more other expansion joint spaces. These intersection joint spaces are found at the juncture of a plurality of building structures, such as when four walls meet to create a cross-wise gap, or where two exterior walls and an interior wall meet creating a “T”-shaped gap. Such multi-directional expansion joints require multi-directional fire barriers as it is structurally impossible for straight line barriers to accommodate the multi-directionality of multi-dimensional intersection joint spaces. Presently, the fire barrier industry is able to provide only jerry-rigged, untested, fire barriers for multi-directional expansion joints. These jerry-rigged barriers are constructed, on-site, from spliced together parts of straight line barriers. It is well-accepted, however, that spliced joints are weak joints. The seams created by splicing are not air-tight and, thus, would allow hot air, smoke, toxic gases, and the like to travel throughout the interior joints of a building greatly reducing any effective time fire-fighters have to get to the fire or for people to leave the burning structure in safety. In addition to being pre-assembled to fit the various multi-dimensional expansion joints, fire barriers should be capable of accommodating the complex differential movement building structural units undergo and be able to retain their resiliency over an extended period of time under dynamic conditions. On-site spliced fire barriers cannot be fire or cycle tested. Additionally, site assembly is time consuming and requires more than one installation person increasing the total construction cost. Because of the inherent weakness of spliced barriers, they are unlikely to hold under even mild stress conditions. During a fire event, building joints are likely to be subject to even greater stress than usual, thereby making it essential that the fire barriers retain their integrity to prevent the migration of gases, flame, and smoke.
In many instances, fire barriers are draped into a joint space with planned for excess side material overlapping the edges of a building unit, such as the top ends of a wall unit. Attachment means, such a screws or bolts are inserted into the top ends of the wall units through the overlap fire barrier material to provide a means of securing the fire barrier to the wall. There are situations, however, where the building specifications do not permit attachment means extruding from the top ends of wall units, for example. In this case, the fire barriers should be “inside-mounted,” that is, the opposing sides of a barrier that is forming a “U” between two wall units will serve as the material through which mounting means will be secured into the building units during the installation process.
Presently available tested fire barriers and the on-site spliced barriers are often the cause of installer injury. Fire barriers usually comprise at least a sheet of stainless steel foil. As each fire barrier has to be handled by the installers the arms and hands of the installers often suffer injury from the sharp protruding edges of the stainless steel foil. Moreover, whenever a fire barrier made with some type of fiber glass material or the like is jerry-rigged on-site, the cutting process emits fibers, some of which are small enough to be breathable creating a breathing air hazard. What is needed are not only pre-assembled fire barriers, but an installation tool that reduces or eliminates direct handling of the barriers. More over, to save cost the installation tool should be low cost, size-adjustable and reusable.
One way to insure that installed fire barriers prevent the passage of smoke, gas, heat, or flame from traveling through the barrier from one floor to another, for example is to ensure that the sides of the barrier (the sides forming the “U” of the installed barrier) are secured tightly to the sides of the building units leaving no gaps between the barrier and the building unit. It would be a great asset to have a means for press-fitting the barrier to the building units as they are readied for the barrier to building unit attachment means to secure the barrier to the building units.
It is clear then that a fire and cycle tested, pre-assembled, straight-line and multi-directional fire barriers constructed as single-piece, continuous units requiring no on-site splicing and providing for one-step, drop-in inside-mount installation by one person into multi-directional joints to prevent the migration of gases, flame, and smoke as well as providing for inside-mounting are urgently needed. Also clearly needed are re-useable, size-adjustable installation tools that provide for one person, one-step, drop-in installation of pre-assembled, continuous, multi-directional/multi-dimensional fire barriers that require no splicing.